The invention relates to a sharing system and a sharing method for an internet-of-things device. The sharing system comprises a shared internet-of-things device, a service device, a sharing rule designing user, a shared user and a sharing control rule input device, wherein the service device comprises a sharing control rule verification module and a sharing control execution module, the sharing control execution module is connected with the sharing control rule verification module, the sharing control execution module sends a message to the shared user to inform the shared user, thereby, the shared user can know that a control rule of the shared internet-of-things device is already shared to the shared user, and when the shared user logs in the service device, the shared user can automatically obtain a corresponding permission to the shared internet-of-things device in accordance with the regulations in the sharing control rule. Compared with sharing systems and sharing methods in the prior art, the sharing system and the sharing method for the internet-of-things device have the advantages that the permission of the internet-of-things device can be shared to other users within the internet for usage, internet open sharing feature can be really reflected, and the idea of making the best use of everything and saving resources is reflected.